Nonaqueous aerosol foams containing mineral oil



United States Patent ()fi Fice 3,419,658 N ONAQUEOUS AEROSOL FOAMS CONTAINING MINERAL OIL Paul Amsdon Sanders, Wilmington, Del., assignor to E. I.

du Pont de Nemours and Company, Wilmington, Del.,

a corporation of Delaware No Drawing. Filed Jan. 25, 1965, Ser. No. 427,940

3 Claims. (Cl. 424-45) ABSTRACT OF THE DISCLOSURE An aerosol foam composition consisting essentially of:

(a) White mineral oil,

(b) From 1 to 10% by weight of at least one surfactant having the structure RO(CH CH O),,H wherein R is an aliphatic hydrocarbon radical selected from the group consisting of (1) saturated alkyl radicals of from 12 to 18 carbon atoms and (2) nonsaturated alkenyl radicals of from 12 to 18 carbon atoms, n is from to 20; and

(c) From 5 to 50% by weight of an aerosol propellent selected from the group consisting of hydrocarbons and chlorofluorohydrocarbons, said propellent having a boiling point between 50 C. and +15 C.

The present invention is directed to novel mineral oil aerosol foam compositions. In particular, this invention is concerned with compositions of mineral oils, certain specified surfactants and aerosol propellents which foam when discharged from aerosol containers.

Production of foams by discharge from aerosol containers is well known. For example, US. Patent 2,655,480 discloses a number of aqueous systems and Canadian Patent 678,079 discloses a number of nonaqueous systems based on polyols. Prior to the present invention, foam producing compositions based on mineral oils have not been described. Such compositions would have many valuable uses as hereinafter described.

It is, therefore, an obiect of the present invention to provide, for the first time novel nonaqueous aerosol foams containing mineral oils.

These. and other objects will be apparent in the present specification which follows.

More specifically, the present invention is directed to novel aerosol foam compositions comprising white mineral oil, from 1% to by weight of a surfactant of structure RO(CH CH O),,H wherein R is an aliphatic hydrocarbon group of 1218 carbons chosen from saturated alkyl and nonsaturated alkenyl groups and n is from O to 20, and from 5% to 50% by weight of an aerosol propellent chosen from hydrocarbon and chlorofiuorohydrocarbon having boiling points of from 5 0 C to 15 C.

A preferred embodiment is one wherein said surfactant 3,419,658 Patented Dec. 31, 1968 The compositions of this invention comprise three essential ingredients, (A) the mineral oil, (B) a surfactant, and (C) the propellent. Mineral oil is usually a white, i.e., highly purified, mineral oil. This is necessary since most intended uses involve application to the human epidermis. Useful mineral oils are commercially available in a wide variety of viscosities, i.e., Saybolt viscosities F.) of 55-400. All such oils are useful because the choice of mineral oil depends primarily on the final product desired, but has a limited effect on the ability to foam, except as the nature of the propellent is efiected.

The useful surfactants are those of structure R may be either an alkyl group of 12-18 carbons or a monounsaturated alkenyl group of 12-18 carbons. In the surfactants, n may vary from 0 to about 20. The surfactants are thus hydrocarbon alcohols or ethoxylated products thereof. Both types are well known in the art and commercially available. While R may be any alkyl or alkenyl group of the type herein defined, the straight chain groups derived from fatty acids by reduction are preferred. Typical examples are lauryl, myristyl, cetyl, stearyl, and oleyl alcohols. The ethoxylated products where n: l-20 are prepared by reaction of these alcohols with ethylene oxide by well known procedures.

The nature of the surfactant has an effect on the nature of foam produced. In general, as the relative amount of the ethylene oxide (the value of n) increases in the surfactant, the relative stability of the foam decreases. Thus, if highly stable foams are desired, the alcohol surfactants containing no ethylene oxide are preferred. On the other hand, if immediate collapsing foams are desired, the surfactants containing relatively large amounts of ethylene oxide are preferred. Both types of foams are useful for a number of purposes. The stable foams are useful in cleansing creams and like applications while the rapidly collapsing foams are useful in medicinal applications, suntan creams and the like where application as a foam is desired, but a persistent foam is not.

Mixture of surfactants may be used. In particular, an equal weight mixture of cetyl and stearyl alcohol has been found to be particularly useful. Where stable foams are desired, this mixture is the preferred surfactant of this invention.

At least 1% by Weight of the total composition of surfactant, oil and propellent must be surfactant if foams are to be obtained. As high as 10% surfactant has been used and larger amounts probably could be used, but there seems to be no advantage in so doing. For most purposes the preferred surfactant concentration is from 3 to 6%.

The propellents used in this invention are chosen from hydrocarbons and chlorofiuorohydrocarbons for boiling points between 50 C. and +15 C. Since the mineral oils vary in viscosity the propellents must be varied in vapor pressure accordingly to produce the most efficient results. The higher the viscosity of the mixture, the greater vapor pressure is required to propel the foam material from the container. The hydrocarbon propellents include propane, butane and isobutane. The chlorofluorohydrocarbon propellents include dichlorodifluoromethane, dichlorotetrafluoroethane, 1,1, l-chlorodifluoroethane, 1,1- difiuoroethane, mixtures of dichlorodifluoromethane and dichlorotetrafiuoroethane, mixtures of dichlorodifiuoromethane and trichlorofiuoromethane, monochloropentafiuoroethane, 1,1,1 trifluoroethane, s-tetrafluoroethane, pentafluoroethane, l-chloro-l,1,2,2-tetrafluoroethane, perfluorocyclobutane, perfluoropropane, chloroheptafluoroand finally pressure loading the propellent in the indicated amount. All of these compositions contain 79% mineral oil of Saybolt viscosity 200-210 seconds, 6% surfactant and 15% CF Cl propellent, all by weight. The conditions and results obtained are shown in Table I.

propane and heptafiuoropropane. Mixtures of the above EXAMPLE 2 hydrocarbons and the chlorofiuorohydrocarbons may also be used. In addition, small amounts of inert gases such as h example Illustrates the effect of the nitrous oxide or carbon dioxide may also be added if reactive amounts of cetyl and stearyl alcohols in mixtures sired. there ofl use? as srilrfafctahnts. The procedure of Exainple l The amount of propellent used naturally varies with 10 was fOIPWe f 0 t e composmons agam con ammg the actual system being produced. In general, less than 79% mmeral 6% Surfactant and CFZCIZ 5% propellent will not produce useful results. As much pellent The results are shown In Table as 50% propellent has been used particularly with the EXAMPLE 3 low vapor pressure propellents. More than 50% propellent could possibly be used but seems to serve no known 15 This example illustrates the effect of varying surfactant useful purpose. The preferred propellents are dichlorodiconcentration. The compositions were prepared using the fiuoromethane, mixtures of dichlorodifluoromethane and procedure of Example 1 at the surfactant concentrations monofiuorotrichlorornethan-e, dichlorotetrafluoroethane, indicated in Table III. The surfactant in each case is a and mixtures of the same with dichlorodifluoromethane 50/50 mixture by weight of cetyl and stearyl. alcohols. because of their lack of flammability. With few excep- The results are shown in Table III. tions, the propellents are soluble in the mineral oil base. The surfactants are usually isoluble. The compositions are EXAMPLE 4 Prepared by Warming the minera1 oil and Surfaftant This example illustrates the effect that different progether with agitation untll thesurfactant has dissolved. penahts have on the results The formulations prepared Depending on the p of equlpmeht Y the by the method of Example 1, each contained 79% min- Surfactaht mixture y be elthel' combined Wlth a P eral oil, 3% cetyl alcohol, 3% stearyl alcohol and 15% pellent, then added to an aerosol container followed by propanent by Weight The results are Shown in Table IV. capping with a foam valve, or by adding the oil-surfactant mixture to the aerosol container, capping with the EXAMPLE 5 foam valve pressure adding the propcll.mt' This example illustrates the effect of changes in pro- The following representative examples illustrate the pellent concentranon. The formulations, prepared by the present invention.

EXAMPLE 1 method of Example 1, each contain 3% cetyl. alcohol, and 3% stearyl alcohol by weight as surfactants. The This example illustrates the use of a variety of survariation in propellent concentration on the results 0bfactants and the effect these have on the resulting foams. tained are shown in Table V.

TABLE I Surfactant Appearance of Aerosol Type of Foam Po1awax" (ethoxylated stearyl alcohol) Many agglomerates Large bubble size, stable foam. Bllj 3O C 2Hz5O(CHsCH2O)4H Clear DO. Brij 52 C sHssO(CH2CH2O)2H .do Wet,dl iqg1i1d foam that collapses im- Brij 56 C HaaO(CH2CH20)i0H Good dispersion of solid... Fd i n ri ol la p ses immediately after dis- "Blij 58 CmHssOKJHzCHzOlmH .d0 o f Brij 72 CIEHB70(CHECHZO)2H. Clear Typical large bubble size, stable foam.

Good dispersion of solid..-

Briy' 78 C13H3:O(CHZCH2O)NH Poor dispersion of solid, Collapses immediately.

cakes on bottom.

Bri1 92 oleyl O(CH2CH;O); H Clear Do.

"BriJ" 96 oleyl O(CH2CH2O)10H Liquid dispersion. Do.

Brij 98 oleyl O(CH2CH20)90H Good Do.

(etyl alcohol/stearyl alcohol (/50) do Large bubble size foam.

Lorol" 34 (Cetyl alcohol) ..do

Very large bubble size, stable. particles.

biponic E-l (ethoxylated stearyl-cetyl Almost clearhazy.. Do.

alcohol. 2 ethylene oxide units). Myristyl alcohol Clear Medium size bubble size foam that collapses within about 30 seconds.

1 Brij surfactants are marketed by Atlas Chemical Industries, Inc. Siponic surfactants are marketed by Alcolac Chemical Corporation. Lorol 24 cetyl alcohol and Lorol 28 stearyl alcohol are products of the Du Pont; Company.

2 Tested with high viscosity mineral oil (Saybolt viscosity 345-355).

The compositions were prepared by heating the liquid oils and surfactants together until solution occurred, cooling the solution, placing it in an aerosol container, sealing the container with a commercially available sealing valve Polywax is a creamy, waxlike solid with a melting range of 48-52 C., iodine value of 3.5 maximum and a saponification value of 9-14. (American Perfumer and Cosmetics, vol. 79, N0. 3, March 1964, p. 56.)

Large bubble size that collapses slowly.

TABLE II Mineral Oil Cetyl alcohol ratio/ Form of Dispersed Solid Type of Foam Stearyl alcohol 100/0 Plates 75/25 Almost completely soluble. Very large bubble size, unstable. 50/ 50 Amorphous Large bubble size. /75 Plates.-. 0/100 .-d0 100/0 d0 75/25 Almost amorphou Very large bubble size, unstable. /50 Amorphous Large bubble size. 25/75 Amorphous and plate 0/100 Plates 100/0 /25 Very large bubble size. 50/50 Large bubble size. 25/75 0/100 /0 75/25 Amorphous a Do. 50/ 50 Amorphous. Do. 25/75 Mostly plates 0/100 Plat 100/0 .d 75/25 Agglom Do. 50/50 Amorphous- Do. 25/75 Mostly plates 0/100 Plat 100/0 75/25 D0. 50/50 Do. 25/75 Large bubble size, unstable. 0/100 100/0 Large bubble size. 75/25 D0. 50/ 50 Amorphous Do. 25/75 Mostly plates Do. 0/ 100 Plates 100/0 Plates (good dispers n) Do. 75/25 Some agglomerates Do. 50 50 Amorphous Do. 25/75 Mostly plates Do. 0/ 100 Plates Do.

I These foams flashed over the surface after discharge and then collapsed.

TABLE III Composition (Wt. percent) Surfactant Mineral oil Ptopre llilt Appearance of Aerosol Type of foam 2 2 Type Conc.

1.0 Low viscosity 84.0 15.0 Clear No foam. 1.0 High viscosity 84. 0 15.0 do Large bubble size, collapsed immediately after discharge. 2.0 Low viscosity"... 83.0 15.0 ..do Large bubble size, very unstable. 2.0 High viscosity. 83.0 15.0 do Largeihigblble size, collapsed imme la e y. 3.0 Low viscosity 82. 0 l5. 0 Few agglomerates present--. Slight foam, unstable. 3.0 82.0 15.0 Poor dispersion of solid Large bubble size foam. 4.0 81. 0 15. 0 Poor, many agglomerates. Do. 4.0 81. 0 15.0 Good dispersion of solid- Do. 5.0 80.0 15.0 Many agglomerates Do. 5.0 80.0 15.0 Good dispersion of solid Do. 0.0 79.0 15.0 do 0 D0. 6.0 High viscosit 79. 0 15.0 Do.

1 Low viscosity mineral oil Saybolt Viscosity, 50-60 seconds. 2 High viscosity mineral oil Saybolt Viscosity, 345-355 seconds.

TABLE IV Propellent Mineral oil Appearance of Aerosol Type of Foam CFQCI: Low viscosity Good dispersion of solids Large bubble size. CFzClg High viscosity 2 do Do. CFzCl2/CFgClCF:Cl(40/60)- Low viscosity .do D0. CFzCh/CFzClCFgCK40/60) High viscosity .do Do. CFzClCFzCl Low viscosity do .i No foam, insuificient pressure.

High viscosity ..do Large bubble size.

Low viscosity Opaque, very few solid particles- Very large bubble size. High viscosity Good dispersion of solids Large bubble size. Low viscosity..-" Poor dispersion, many solid aggregates. Very large bubble size. High viscosity Good dispersion of solids Large bubble size.

Low viscosity Gelled in container High viscosity do Low viscosity Poor dispersion, many solid aggregates.

Rough surface foam. Large bubble size.

High viscosity Good dispersion of solids Do. Low viscosity Cloudy, opaque dispersion. in Rough surface foam. High viscosity Fair dispersion, some aggregates Do.

1 Low viscosity mineral oil=Saybolt viscosity 50-60 seconds. 2 High viscosity mineral oil=Saybolt viscosity 350 seconds.

\ Low Viscosity oil, Saybolt Viscosity 50-60 secs. 2 High Viscosity oil, Saybolt Viscosity 345-355 secs.

Appearance of aerosol All of the products have good dispersions of the solids. The viscosity decreases as the propellent concentration increases. Formulation No. l is fairly fluid while Formulation No. 7 is almost a gel. Formulation No. 2 and Formulation No. 8 are fairly fluid.

Type of foam Formulation No. 1 does not produce a foam due to insufficient pressure. Formulation No. 7 gives a low foam. The formulations with 15% and 20% propellent give very pressure-sensitive foams while those with 25% and 50% propellent give much more coherent and less pressuresensitive foams.

The preceding representative examples may be varied within the scope of the present total specification disclosure as understood and practiced by one skilled in the art to achieve essentially the same results.

As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that this invention is not limited to the specific embodiments thereof except as defined in the appended claims.

The embodiments of the invention in-which an exclusive property or privilege is claimed are as follows.

I claim:

1. An aerosol foam composition consisting essentially of:

(a) white mineral oil,

(b) from 1 to 10% by Weight of at least one surfactant having the structure RO(CH CH O) H wherein R is an aliphatic group selected from the group consisting of (1) alkyl of from 12 to 18 carbon atoms and (2) alkenyl of from 12 to 18 carbon atoms, n is from 0 to 20; and

(c) from 5 to 50% by weight of an aerosol propellant selected from the group consisting of hydrocarbons and chlorofiuorohydrocarbons, said propellant having a boiling point between 50 C. and +15 C.

2. An aerosol foam composition according to claim 1 wherein said surfactant is a mixture of cetyl and stearyl alcohols.

3. An aerosol foam composition according to claim 1 wherein said surfactant is a 50/50 by weight mixture of cetyl and stearyl alcohols.

References Cited UNITED STATES PATENTS 2,942,008 6/1960 Lubowe 16782 X 3,131,153 4/1964 Klausner 252305 3,330,730 7/1967 Hernandez 16782 X FOREIGN PATENTS 933,486 8/1963 Great Britain.

ALBERT T. MEYERS, Primary Examiner.

V. C. CLARKE, Assistant Examiner.

US. Cl. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,419,658 December 31, 1968 Paul Amsdon Sanders It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 8, line 16, "50 (3." should read -50 (3.

Signed and sealed this 17th day of March 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr.

Attesting Officer Commissioner of Patents WILLIAM E. SCHUYLER, JR. 

